This invention relates to a system using storage media such as an IC card having an electronic circuit chip mounted therein or a magnetic recording card.
With the progress in miniaturization and thickness reduction of integrated circuit chips, a variety of new uses for such have been proposed. In Japanese Patent Laid-open No. Hei 3-38396, a technique is described for utilizing an electronic circuit chip for storing information by mounting the chip on a card along with an antenna device to allow information to be read from the chip by a non-contact reading technique. By storing information about the owner of such a card in a chip mounted on the card, the card can be used as an ID card. In addition, by storing information about an item to which such a card is attached, the card can be used as a tag of the commodity.
The amount of information that can be stored in an electronic circuit chip mounted on a card depends on the size of the card. The larger the amount of information required to be stored in the chip, the larger the size of the card. Because a large card is less portable, if portability is of importance, it is necessary to reduce the size of the card. A small card, however, allows only a small chip with a small amount of information. These relationships apply not only to a card using an electronic circuit chip, but also other storage media such as a magnetic recording card.
To allow information to be stored on a card having an electronic circuit chip, a RAM (Random Access Memory) or other writable memory must be included in the electronic circuit chip. In general, RAM is large and expensive in comparison with a ROM (Read-Only Memory). Thus, a card having an electronic circuit chip including RAM is less portable, and more expensive.